Liquid crystal diode (LCD) display packages typically include a display assembly, a backlight which provides light to the display assembly, and processing and graphics electronics which are configured to drive the TFTs. The backlight and processing and graphics electronics, and to a lesser extent the display assembly, generate heat. In order to reduce the operating temperature of the LCD display package, the package often further includes a heat sink disposed between, and thermally in contact with, the backlight and the processing and graphics electronics.
OLED display packages have an advantage over other display packages, such as LCD display packages, which require a backlight. Color OLED display packages generally comprise a display assembly including control circuitry and an array of pixels, where each pixel has a plurality of subpixels, and each subpixel for a particular pixel is of a different color, and has an OLED. The display assembly control circuitry manages the voltage to be applied to each subpixel where the luminance of a subpixel increases with the voltage applied. The processing and graphics electronics, which is separate from the display assembly, provides power and content to be applied to the display assembly.
The luminance of the OLED subpixels degrades with time. OLEDs often suffer from a reduced useful lifetime especially when operated for extended periods of time at maximum luminance. Luminance degradation is further accelerated at elevated temperatures. The luminance degradation is exacerbated in environments where the OLED display package is desired to be operated at near maximum luminance.